Revox B261 Serviceanleitung Seite 49

sT[JDtrR Rd/OX
8261 SA
sEciloN
4/8x
4.7.8 Adjusting the
10 kHz
cross-talk rejection
- Set stereo standard-signal- generator to
98.0 MHz, 40
k}Jz
deviation, modulation
1"0
kHz
(left = right),
modulate
onJ-y
right-hand
channel
of stereo modulator,
and
adjust for
maximum
cross-tal-k rejection with L6 (<40
dB).
4.8 Adjusting the audio
PCB
1.726.821,/820
Required
test
equipment:
- Stereo
standard-signal generator with stereo
modulator
-
AF
voltmeter
- Digital
voltmeter
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Fig. 4.9
MP18
R25 R23
- Connect stereo standard-signal
generator to antenna input
and
feed 2
mV
EMF,
98.0 MHz, 75 kHz deviation, modulation 400
Hz
without pilot
tone.
- Connect AF voltmeter to
OUTPUT
FIXED
L (R) and adjust
R44
(R23) to 2
V.
- Press
CAL
TONE
400
Hz button [181.
- Connect digital voltmeter to test point
MP18
and adjust
R25
to -0.5
V.
4.9 Adjusting the display
1.726.840
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tlta
r&ß(gla
lglälgtgj
R44
Required test equipment:
- DigitaJ- voltmeter
Adjustment procedure:
-
Rernove
larnp shield so that the display
- Connect digi-tal voftmeter to test point
to 3.I V +0.1- V (DC).
PCB
becomes
accessible
MP19
and adjust
R7
t,,t
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MP19
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NjlF
(crL
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AY
R7----+
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1\_-./
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GID
Fig. 4.10